Dual role (also known as double role) refers to one actor playing two or more roles, which may be deliberately scripted in a play or film, or merely be a by-product of a low budget. In a theatrical production where more than one actor plays multiple characters, it is sometimes referred to as an "Ironman" cast. In film and television, a dual role is commonly used either for comic effect or to depict identical twins.
In theatre, such as in the works of absurdists such as Tom Stoppard, characters played by the same actor may be of thematic significance. A good example of this is Tony Kushner's Angels in America, which has a cast of eight despite having many roles. Debate exists over William Shakespeare's use of such, with a famous example being whether the characters of Cordelia and the Fool in King Lear are one and the same. In stage productions of Peter Pan, it is a tradition for Mr. Darling and Captain Hook to be played by the same actor, a tradition often continued in film adaptations with the actors playing dual roles.
In film, this technique has often been used for comic effect, examples being Peter Sellers in movies such as Dr. Strangelove and Mike Myers in the Austin Powers films. In The Wizard of Oz the farmhands also play the parts of the Tin Man, Cowardly Lion and Scarecrow. The Prisoner of Zenda, with its tale of lookalikes, has a long tradition of dual roles: from Lewis Stone (1922) to Ronald Colman (1937) to Stewart Granger (1952) to Peter Sellers (1979). An early and unusual example is the 1925 silent film Lady of the Night. Two women are portrayed by Norma Shearer to spotlight their very different social classes; otherwise, nobody takes any notice of their identical appearance. Lee Marvin won an Academy Award for Best Actor for his dual role in Cat Ballou, while Nicolas Cage was nominated for Adaptation.
More extreme cases exist. Buster Keaton played nearly every part in his 1921 film The Playhouse. Alec Guinness brought to life all eight members of one family in Kind Hearts and Coronets. Likewise, in The Nutty Professor and its sequel, Eddie Murphy played the title character and almost every member of his family.
In Bollywood, having a living double in a film "almost a genre in itself," according to filmmaker Govind Nihalani. Angoor (1982) features two pairs of identical twins, played by Sanjeev Kumar and Deven Verma. Tamil film actor M. N. Nambiar played eleven parts in the early 1950s film Digambara Samiyar, as sage 'Digambar Saamiyar' who take 9 disguises to defeat an evil lawyer. Another Tamil Indian film actor, Kamal Hassan, had ten roles in the 2008 film Dasavathaaram (The Ten Avatars). Sivaji Ganesan played nine roles in the Tamil film Navarathiri. Priyanka Chopra played the roles of 12 eligible girls in the movie What's Your Raashee?. Mehmood Ali portrayed 3 generations of the Kapoor family (Prithviraj Kapoor, Raj Kapoor and Randhir Kapoor) in the movie Humjoli.
In some cases of low-budget films, or community theater, actors may play more than one role to save money. In one of Peter Jackson's early films, Bad Taste, he played two characters; in one scene, one of them tortures the other.
In television, soap operas commonly use the technique to either portray twins (or even similar looking relatives), or to bring an actor back whose character has been killed. This technique is uncommon, although not unheard of, in primetime television. In Friends, Lisa Kudrow plays Phoebe and her twin sister Ursula. David Schwimmer played a character in heavy make-up named Russ, who was a parody of Ross (played by Schwimmer), both of whom appear on screen together. In the Star Trek episode called "Mirror, Mirror", the officers of the Enterprise switch places with their counterparts from a parallel universe, with the actors playing dual roles.